The present invention relates to improvements in multiple-spindle automatic bar machines, and more particularly to improvements in apparatus for feeding elongated bar-shaped workpieces into the work spindles of such machines. Still more particularly, the invention relates to improvements in automatic work feeding apparatus for use in or with multiple-spindle automatic bar machines.
It is already known to utilize in or with a multiple-spindle bar machine a work feeding apparatus wherein a drum or turret is located behind and is indexible with the carrier for work spindles. The drum is connected with and indexes elongated tubular guides each of which registers with a work spindle and each of which can receive a bar-shaped workpiece so that the workpiece therein can be fed into and through the respective work spindle. The feeding apparatus further comprises a single advancing member or pusher which can engage a workpiece in one of the tubular guides to shift the engaged workpiece lengthwise toward and into the registering work spindle. A drawback of such feeding apparatus is that the length of working strokes which the pusher can perform is limited; this is the main reason that the feeding apparatus can operate properly only if the length of all workpieces is identical or nearly identical. As a rule, the differences in the length of workpieces cannot exceed 20 millimeters.